Abstract

Non‐rainfall water inputs (NRWIs) are the least studied hydrological components in most ecosystems. These NRWI components
potentially play an important role in ecosystem dynamics and are particularly important for water‐limited systems. In this
review, we summarized recent advances investigating the effects of NRWIs on various ecosystem functions, including vegetation‐water
relations, biogeochemical cycling, groundwater recharge, as well as reptile and invertebrate adaptations. We also identified
key knowledge gaps such as the mechanisms of NRWIs alleviating vegetation water stress, sources of the NRWI components and
their quantitative contributions to ecosystem functions. To better predict the ecosystem responses to climate change especially
in drylands, a better understanding and quantification of NRWI contributions is essential. WIREs Water 2017, 4:e1179. doi: 10.1002/wat2.1179

This article is categorized under:

Water and Life > Nature of Freshwater Ecosystems

Science of Water > Hydrological Processes

Science of Water > Water Extremes

Images

The known non‐rainfall water use of different organisms (the sizes of organisms are not to scale). The numbers underneath each organism category are the selected references on this topic.

A global distribution of the past research work that focus on non‐rainfall inputs (i.e., fog, dew, and water vapor adsorption) in both dryland and non‐dryland ecosystems. AI represents aridity index, which is defined as the ratio of precipitation and potential evapotranspiration.

McKay, CP, Friedmann, EI, Gómez‐Silva, B, Cáceres‐Villanueva, L, Andersen, DT, Landheim, R. Temperature and moisture conditions for life in the extreme arid region of the Atacama Desert: four years of observations including the El Niño of 1997–1998. Astrobiology 2003, 3:393–406.

Feild, TS, Dawson, TE. Water sources used by Didymopanax pittieri at different life stages in a tropical cloud forest. Ecology 1998, 79:1448–1452.